KR102639074B1 - Method and Apparatus for Preventing Relay Contact Fault - Google Patents

Abstract

The present invention relates to a method and device for preventing relay contact failure in a vehicle. According to an embodiment of the present invention, a relay contact failure prevention device connected to an in-vehicle communication network and controlling power supply to a load includes a switch and a coil. and a first controller that determines whether the relay contact is welded based on the relay and the signal application state of the relay and the output voltage of the relay, and when welding of the relay contact is detected, the first controller A signal can be applied to the coil of the relay.

Description

{Method and Apparatus for Preventing Relay Contact Fault}

The present invention relates to prevention of relay contact melting in vehicles, and more specifically, to a relay contact factory prevention method and device that can detect and solve problems of welding phenomenon and poor current conduction of vehicle relay contact points.

Today, due to high oil prices and carbon dioxide regulations, the development of eco-friendly vehicles that can replace existing internal combustion engine vehicles is actively underway. Recently, pure electric vehicles that run by driving an electric motor or use a combination of an internal combustion engine and an electric motor as a driving source are in progress. Depending on the automobile manufacturer, hybrid cars have already been commercialized or are about to be commercialized.

Electric vehicles and hybrid vehicles are equipped with a high-voltage battery as the main power source to supply power to the electric motor (traction motor), which is the driving source, and in addition, a charging device for charging the battery and an electric motor (hereinafter referred to as 'drive motor'). ) is equipped with an inverter to drive it.

The inverter converts the power supplied from the high-voltage battery according to a control signal from a motor control unit (MCU) to drive the driving motor. In addition, a battery management system (BMS) is installed to monitor the status of the battery. This battery controller collects battery status information about the battery's temperature, voltage, charge/discharge current, and battery SOC (State of Charge). , the collected battery status information is provided to other controllers in the vehicle so that it can be used for vehicle control. In particular, the battery controller checks the battery status and manages the battery status to maintain a certain level or higher, prevents shortening of lifespan due to deterioration of battery durability, and informs the vehicle controller that performs total control of battery SOC information to determine the battery status. Ensure that vehicle driving takes into account.

Hybrid vehicles ultimately have the main purpose of realizing a highly efficient vehicle by increasing fuel efficiency and creating an eco-friendly vehicle by improving exhaust performance.

Power transmission in a hybrid vehicle may be achieved by having an engine, a motor, and an automatic transmission directly connected on one axis, and a clutch is arranged between the engine and the motor. And, as a configuration for these operations, a hybrid battery (i.e., high-voltage battery) is connected to the motor through an inverter to enable charging and discharging. In this way, a high-voltage battery is used in a hybrid vehicle, and to protect this hybrid battery, a relay that is usually connected in series to the load and disconnects and connects a large current can be used.

In the above description, the case where the load is a high-voltage battery carrying a relatively high current is given as an example, but a relay may be used to control a load carrying a relatively small current and a start-up load. For example, loads carrying small currents may include wipers, LED lamps, etc., and starting loads may include fuel pumps, starters, etc.

When these relays are in use, high voltage may flow in the circuit if the contact parts fuse together.

In particular, in the past, due to package problems, the percentage of PCB (Printed Circuit Board) relays used was increasing, but there was a problem that the entire junction block or ICU (Immobilizer Control Unit) had to be replaced when the PCB relay was defective.

Therefore, there is a need for a relay contact failure prevention method and device to solve the problem when detecting fusion of relay contacts and to effectively solve the current conduction failure phenomenon caused by the oxide film.

The present invention was designed to solve the problems of the prior art described above, and the purpose of the present invention is to provide a method and device for preventing relay contact failure in a vehicle.

Another object of the present invention is to provide a relay contact failure prevention method and device that can eliminate the welding phenomenon at the relay contact by controlling the relay switch before the relay contact is cooled when the welding state of the relay contact is detected. .

Another object of the present invention is to provide a relay contact failure prevention method and device that can solve the problem of poor current conduction by applying overcurrent to the relay switch with poor current conduction using a provided overcurrent conduction circuit when poor conduction of the relay contact is detected. is to provide.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below. You will be able to.

The present invention provides a method and device for preventing relay contact failure in a vehicle.

A relay contact failure prevention device connected to an in-vehicle communication network and controlling power supply to a load according to an embodiment of the present invention includes a relay including a switch and a coil, a signal application state of the relay, and an output voltage of the relay. and a first controller that determines whether the relay contact is welded based on the welding of the relay contact, and when welding of the relay contact is detected, the first controller may apply a signal to the coil of the relay.

According to another embodiment of the present invention, a relay contact failure prevention device connected to an in-vehicle communication network and controlling power supply to a load includes a relay including a switch and a coil, the signal application state of the relay, and the output voltage of the relay. It includes a first controller that determines whether or not conduction is defective at the switch contact based on the overcurrent conduction circuit, which is connected in parallel with the load and absorbs a large current passing through the switch according to a control signal from the first controller; , when an energization failure at the switch contact point is detected, the first controller may control the large current to flow to the switch of the relay.

A method for preventing relay contact failure in a device connected to an in-vehicle communication network and controlling power supply to a load according to another embodiment of the present invention includes the steps of measuring a relay output voltage, the signal application state of the relay, and the It may include determining whether the relay contact is welded based on the relay output voltage, and applying a signal to the coil of the relay when welding of the relay contact is detected as a result of the determination.

In addition, the relay contact failure prevention method includes the steps of determining whether the switch contact of the relay has a poor conduction based on the signal application state of the relay and the relay output voltage, and when the poor conduction of the switch contact of the relay is detected, The method may further include controlling a large current to flow to the switch of the relay using an overcurrent conduction circuit.

Another embodiment of the present invention can provide a computer-readable recording medium on which a program for executing any one of the relay contact failure prevention methods described above is recorded.

The above aspects of the present invention are only some of the preferred embodiments of the present invention, and various embodiments reflecting the technical features of the present invention will be described in detail by those skilled in the art. It can be derived and understood based on.

The effects of the method and device according to the present invention will be described as follows.

The present invention has the advantage of providing a method and device for preventing relay contact failure in a vehicle.

In addition, the present invention has the advantage of providing a relay contact failure prevention method and device that can eliminate the welding phenomenon at the relay contact by controlling the relay switch before the relay contact is cooled when the welding state of the relay contact is detected. there is.

In addition, another object of the present invention is to provide a relay contact that can solve the problem of poor current conduction by applying overcurrent to the relay switch with poor current conduction using an overcurrent conduction circuit provided when the poor conduction of the relay contact is detected. There is an advantage in providing a failure prevention method and device.

In addition, the present invention has the advantage of providing a relay contact failure prevention method and device that facilitates tracking the cause of the failure by generating and recording a warning or failure code when the failure problem of the relay contact is not resolved.

Additionally, the present invention has the advantage of reducing replacement costs for parts and controllers due to defective existing relay contacts.

The advantages and effects that can be obtained from the present invention are not limited to those mentioned above, and other effects not mentioned above will become clear to those skilled in the art from the description below. It will be understandable.

The drawings attached below are intended to aid understanding of the present invention and provide embodiments of the present invention along with a detailed description. However, the technical features of the present invention are not limited to specific drawings, and the features disclosed in each drawing may be combined to form a new embodiment.
1 is a diagram for explaining a relay structure in a vehicle according to the prior art.
Figure 2 is a diagram for explaining the structure of a relay contact failure prevention device according to an embodiment of the present invention.
Figure 3 is a diagram for explaining the configuration of a relay contact failure prevention device according to another embodiment of the present invention.
Figure 4 is a flowchart for explaining a method for preventing relay contact failure in a vehicle according to an embodiment of the present invention.
Figure 5 is a flowchart for explaining a method for preventing relay contact failure in a vehicle according to another embodiment of the present invention.

Hereinafter, devices and various methods to which embodiments of the present invention are applied will be described in more detail with reference to the drawings. The suffixes “module” and “part” for components used in the following description are given or used interchangeably only for the ease of preparing the specification, and do not have distinct meanings or roles in themselves.

In the above, even though all the components constituting the embodiment of the present invention have been described as being combined or operated in combination, the present invention is not necessarily limited to this embodiment. That is, as long as it is within the scope of the purpose of the present invention, all of the components may be operated by selectively combining one or more of them. In addition, although all of the components may be implemented as a single independent hardware, a program module in which some or all of the components are selectively combined to perform some or all of the functions of one or more pieces of hardware. It may also be implemented as a computer program having. The codes and code segments that make up the computer program can be easily deduced by a person skilled in the art of the present invention. Such a computer program can be stored in a computer-readable storage medium and read and executed by a computer, thereby implementing embodiments of the present invention. Storage media for computer programs may include magnetic recording media, optical recording media, etc.

In addition, terms such as “include,” “comprise,” or “have” as used above mean that the corresponding component may be included, unless specifically stated to the contrary, and thus do not exclude other components. Rather, it should be interpreted as being able to include other components. All terms, including technical or scientific terms, unless otherwise defined, have the same meaning as generally understood by a person of ordinary skill in the technical field to which the present invention pertains. Commonly used terms, such as terms defined in a dictionary, should be interpreted as consistent with the meaning in the context of the related technology, and should not be interpreted in an idealized or overly formal sense unless explicitly defined in the present invention.

Additionally, when describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the component is not limited by the term. When a component is described as being “connected,” “coupled,” or “connected” to another component, that component may be directly connected or connected to that other component, but there is another component between each component. It will be understood that elements may be “connected,” “combined,” or “connected.”

Figure 1 is a diagram for explaining a method of controlling a relay mounted on an integrated control device of a vehicle according to the prior art.

The conventional integrated control device 110 includes at least one relay (first relay 110 to second relay 120) and a first controller 130 that controls a large current flowing through the relay.

Referring to FIG. 1, the second controller 140 disposed outside the integrated control device 100 controls the operation of the first relay 110 mounted within the integrated control device 100 to control the first load 150. The power delivered to can be controlled.

On the other hand, the first controller 130 mounted inside the integrated control device 100 can control the power delivered to the first load 160 by controlling the operation of the second relay 120.

Through this, the internal processing load of the integrated control device 100 can be distributed. In general, the integrated control device 100 can perform not only a power transfer control function through provided relay control but also a gateway function.

Referring to drawing number 110, each relay may be configured to include a switch and a coil. The controller can control the operation of the switch by controlling the signal applied to the coil.

Figure 2 is a diagram for explaining the configuration of a relay contact failure prevention device according to an embodiment of the present invention.

Referring to FIG. 2 , power supplied from the power source 210 may be transmitted to the first load 220 and the second load 230 through the relay contact failure prevention device 200.

The relay contact failure prevention device 200 may include at least one relay (a first relay 201 and a second relay 202), a first controller 262, and an overcurrent conduction circuit 204. Here, each relay may be configured to include a switch and a coil.

The relay contact failure prevention device 200 according to an embodiment of the present invention may be configured with additional functions of the integrated control device of FIG. 2, but this is only one embodiment and is not limited thereto.

Some relays provided in the relay contact failure prevention device 200 may be controlled by a controller external to the device - for example, the second controller 240.

Referring to FIG. 2, the first controller 203 may control the switch operation of the second relay 202 by controlling a signal applied to the coil of the second relay 202.

On the other hand, the second controller 240 provided outside the relay contact failure prevention device 200 can control the switch operation of the first relay 201 by controlling the signal applied to the coil of the first relay 201. .

The in-vehicle communication network according to this embodiment may include at least one of a CAN communication network, an Ethernet communication network, a Flexlay communication network, a K-Line communication network, and a LIN communication network.

The first controller 203 can exchange control signals and various information with the second controller 240 through the in-vehicle communication network 250. Communication lines established between controllers may include CAN (Controller Area Network) communication lines, K-Line, Flexlay communication lines, Ethernet communication lines, LIN communication lines, etc.

As an example, the first controller 203 may receive signal application status information of the coil of the first relay 201 from the second controller 240 through the in-vehicle communication network 250. The first controller 203 receives the signal application status information of the coil of the first relay 201 received from the second controller 240 and the voltage (Vm) measurement result between the contact point of the first relay 201 and the rear end of the switch. Based on this, it can be determined whether the switch contact of the first relay 201 is welded.

The first controller 203 obtains intensity information about the output voltage of the first relay 201 and the second relay 201 through the first voltage measurement line 261 and the second voltage measurement line 262, respectively. You can. As an example, the relay output voltage may be a voltage measured between the contact point of the corresponding relay switch and the rear end of the corresponding switch, but is not limited to this.

Relay switch contacts may generate heat due to high current flowing through the switch, which may result in welding points being created at the switch contacts. If the molten weld point is completely cooled, normal switch operation may no longer be possible. Therefore, when a signal is supplied to the coil of a relay where a welding phenomenon has occurred before the welding point is completely cooled, magnetic force is applied to the corresponding relay switch, which may remove the welding point of the corresponding relay switch. At this time, a signal may be repeatedly supplied to the corresponding relay coil a certain number of times.

Of course, if the welding phenomenon is not removed despite repeated signal supply, the first controller 203 records the corresponding fault code in a predetermined recording area and then issues a predetermined warning alarm indicating that the relay welding phenomenon has not been removed. It can be transmitted to the cluster (not shown) via my communications network.

For the convenience of explanation below, the state in which a signal is being applied to the relay coil - that is, the relay switch closed status - is referred to as the "relay signal ON state" and the state in which the signal is being applied to the relay coil - that is, The relay switch open status is referred to as “relay signal OFF status.”

When a welding phenomenon occurs where relay switch contacts are unintentionally stuck, a signal is applied to the relay coil and the welded switch moves, but the current transmitted to the load through the switch may be very small. This may be caused by excessive switch end resistance due to the oxide film formed on the switch end. In order to remove the oxide film formed on the switch end, an overcurrent must be passed to the switch.

The first controller 203 according to an embodiment of the present invention may control the overcurrent conduction circuit 204 so that an overcurrent is passed to the switch of the corresponding relay when an energization failure is detected while the relay signal is in the ON state. Here, when the voltage of the output terminal of the corresponding relay switch exceeds a predetermined high voltage reference value while the relay signal is in the ON state, the first controller 203 may determine that an energization failure has occurred in the corresponding relay switch.

The overcurrent conduction circuit 204 is connected in parallel with the loads 220 and 230, and when the operation of the overcurrent conduction circuit 240 is activated by the first controller 203, all (or most) of the large current passing through the switch is It may be transmitted to the overcurrent conduction circuit 240 through the overcurrent conduction lines 271 to 272.

If an overcurrent flows through a relay switch in which conduction failure is detected, the formed oxide film may be removed. Since the resistance of the overcurrent conduction circuit 204 is very low, the large current passing through the relay switch is not transmitted to the load, but is transmitted to the overcurrent conduction circuit 204 and may be grounded.

On the other hand, if the energization defect is not resolved despite the passage of the overcurrent, the first controller 203 records the corresponding fault code in a predetermined recording area and then sends a predetermined warning alarm indicating that the relay energization defect has been detected through the in-vehicle communication network. It can be transmitted to a cluster (not shown).

For example, the overcurrent conduction circuit 204 may use a field effect transistor (FET) for overcurrent, but is not limited thereto.

In another embodiment of the present invention, when the load connected to the relay is a variable load, the first controller 203 detects poor conduction, increases the amount of current flowing to the load, and removes the oxide film formed on the relay switch. You may.

In the above-described embodiment of FIG. 2, the second controller 240, which is an external controller connected to the relay contact failure prevention device 200 through a communication line, is shown as being able to control the operation of the first relay 201. In just one embodiment, the relay contact failure prevention device 200 may control the operation of all relays provided.

Figure 3 is a diagram for explaining the configuration of a relay contact failure prevention device according to another embodiment of the present invention.

As shown in FIG. 3, the relay contact failure prevention device 300 may control all relays (first to second relays 201 and 202) provided therein by the first controller 203.

Figure 4 is a flowchart for explaining a method for preventing relay contact failure in a vehicle according to an embodiment of the present invention.

Referring to FIG. 4, the relay contact failure prevention device can monitor whether the relay contacts are welded (S401).

The relay contact failure prevention device can determine whether the relay contact is welded based on the signal application state of the relay coil and the strength of the voltage applied to the relay contact and the rear end of the switch (S402). For example, if the relay switch voltage measured while the signal applied to the relay coil is in the OFF state exceeds a predetermined high voltage judgment standard, the relay contact failure prevention device may determine that a welding phenomenon has occurred at the corresponding relay contact point.

When the relay contact failure prevention device detects relay contact welding, it can apply a signal to the relay coil for a certain period of time (S403).

The relay contact failure prevention device can check whether the relay contact welding phenomenon has been eliminated (S404). Here, when a signal is applied to the relay coil, a magnetic field is formed around the relay switch, and welding points that have not yet cooled can be removed by the magnetic force of the formed magnetic field. When the relay contact failure prevention device confirms that the relay switch voltage has changed to a normal state (i.e., a low voltage state), it can be determined that the relay contact welding phenomenon has been eliminated.

As a result of confirmation, if the relay contact welding phenomenon is eliminated, the relay contact failure prevention device can return to step 401 described above and continue to monitor the relay contact welding state.

As a result of the confirmation in step 404 above, if the relay contact welding phenomenon is not removed, the relay contact failure prevention device may repeatedly turn on the relay coil signal for a certain number of times.

If the number of ON times of the relay coil signal exceeds a predetermined standard value, the relay contact failure prevention device determines that removal of the weld point has failed, records the corresponding failure code in a predetermined recording area, generates a predetermined warning alarm signal, and transmits it to the cluster (S405 to S406). At this time, a warning alarm indicating a defective relay contact may be output to the cluster.

Figure 5 is a flowchart for explaining a method for preventing relay contact failure in a vehicle according to another embodiment of the present invention.

Referring to FIG. 5, the relay contact failure prevention device can monitor the energization state of the relay switch (S501).

The relay contact failure prevention device can determine whether the current is poor at the relay switch contact point based on the signal application state of the relay coil and the strength of the voltage applied to the relay contact point and the rear end of the switch (S502). For example, if the relay switch voltage measured while the signal applied to the relay coil is turned on exceeds a predetermined high voltage judgment standard, the relay contact failure prevention device may determine that an energization failure has occurred at the corresponding relay switch contact point. As another example, the relay contact failure prevention device determines that an energization defect has occurred at the corresponding relay switch contact point when the intensity of the measured current at the rear end of the relay switch exceeds a predetermined energization defect judgment standard value while the signal applied to the relay coil is ON. You can also judge.

When a relay contact failure prevention device detects an energization defect at a relay switch contact point, it can control the overcurrent to be applied to the relay switch in which the energization defect is detected using a provided overcurrent energization circuit (S503). At this time, if overcurrent is applied to the relay switch in which poor conduction is detected, the oxide film formed on the switch contacts may be removed.

The relay contact failure prevention device can check whether the conduction failure phenomenon at the relay switch contact point has been eliminated (S504). When the relay contact failure prevention device confirms that the relay switch voltage has changed from a high voltage state to a normal state (i.e., a low voltage state), it can be determined that the poor conduction phenomenon of the relay switch contact has been eliminated.

As a result of confirmation, if the phenomenon of poor conduction of the relay switch contact point is eliminated, the relay contact failure prevention device may return to step 501 and monitor the current state of the relay switch contact point.

As a result of the confirmation in step 504 above, if the current conduction defect of the relay switch contact point is not eliminated, the relay contact failure prevention device determines that the elimination of the current conduction defect has failed, records the corresponding fault code in a predetermined recording area, and issues a predetermined warning alarm signal. It can be created and transmitted to the cluster (S505). At this time, a predetermined warning alarm indicating poor conduction of relay switch contacts may be output to the cluster. A relay contact failure prevention device according to an embodiment may perform an overcurrent energization procedure using an overcurrent energization circuit by repeating a certain number of times until the energization defect phenomenon is eliminated. If the current conduction failure phenomenon is not eliminated despite repeating the overcurrent energization procedure a certain number of times, the relay contact failure prevention device may perform step 505 described above.

The procedure for detecting and eliminating the current conduction failure phenomenon of FIG. 5 described above may be performed when current does not normally flow through the switch after the welding phenomenon of the relay switch contacts is removed through the method of FIG. 4. It should be noted that this is only one embodiment, and the methods of FIGS. 4 and 5 may be performed in parallel.

It is obvious to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit and essential features of the present invention.

Accordingly, the above detailed description should not be construed as restrictive in all respects and should be considered illustrative. The scope of the present invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention.

Claims (19)

In the relay contact failure prevention device connected to the in-vehicle communication network and controlling power supply to the load,
A relay containing a switch and a coil; and
A first controller that determines whether the relay contact is welded based on the signal application state of the relay and the output voltage of the relay,
The first controller,
A relay contact failure prevention device that applies a signal to the coil of the relay before the welding of the relay contact is cooled when the welding of the relay contact is detected. According to paragraph 1,
A relay contact failure prevention device in which welding of the relay contact is detected when the signal applied to the coil of the relay is turned off and the voltage measured between the relay contact point and the rear end of the switch exceeds a predetermined high voltage judgment standard value. . According to paragraph 1,
A relay contact failure prevention device wherein a plurality of the relays are provided in the relay contact failure prevention device, and the operation of some relays is controlled by another controller connected to the in-vehicle communication network. According to paragraph 3,
The first controller receives relay signal application status information from the other controller through the in-vehicle communication network, and determines whether the relay contact is welded based on the received relay signal application status information and the output voltage of the relay. , relay contact failure prevention device. According to paragraph 1,
A relay contact failure prevention device in which, when welding of the relay contact is detected, the first controller repeatedly applies a signal to the corresponding coil a certain number of times until the welding phenomenon of the relay is removed. According to clause 5,
If the welding state is maintained even after repeatedly applying the signal a certain number of times, the first controller records a predetermined fault code indicating that a relay welding problem has occurred in a predetermined recording area. According to clause 5,
If the welding state is maintained even after repeatedly applying the signal a certain number of times, the first controller transmits a predetermined warning alarm indicating that a relay welding problem has occurred in the cluster through the in-vehicle communication network, preventing relay contact failure. Device. According to paragraph 1,
The in-vehicle communication network includes at least one of CAN communication, Ethernet communication, Flexlay communication, K-Line communication, and LIN communication. In the relay contact failure prevention device connected to the in-vehicle communication network and controlling power supply to the load,
Relays containing switches and coils;
a first controller that determines whether there is a failure of electricity in the switch based on the signal application state of the relay and the output voltage of the relay; and
An overcurrent conduction circuit connected in parallel with the load and absorbing a large current passing through the switch and an overcurrent conduction line electrically connected to the switch in accordance with a control signal from the first controller,
The first controller obtains intensity information about the output voltage of the relay through a voltage measurement line,
A relay contact failure prevention device wherein the voltage measurement line is electrically connected to the overcurrent conduction line. According to clause 9,
A relay contact failure prevention device that detects poor energization of the switch when the signal applied to the coil of the relay is turned on and the voltage measured between the relay contact point and the rear end of the switch exceeds a predetermined high voltage judgment standard value. . According to clause 9,
A relay contact failure prevention device in which, when a poor current in the switch is detected, the first controller controls the large current to pass through the switch repeatedly a certain number of times until the poor current in the relay is eliminated. According to clause 11,
If the conduction failure phenomenon is not eliminated even after repeatedly passing a large current a certain number of times, the first controller records a predetermined fault code in a predetermined recording area indicating that an energization problem of the relay switch contact point has occurred. Relay contact failure prevention device. According to clause 11,
If the energization failure phenomenon is not eliminated even after repeatedly applying the large current a certain number of times, the first controller transmits a predetermined warning alarm to the cluster through the in-vehicle communication network indicating that an energization problem at the relay switch contact point has occurred. A relay contact failure prevention device. In a method for preventing relay contact failure in a device connected to an in-vehicle communication network and controlling power supply to a load,
measuring the relay output voltage;
determining whether the relay contacts are welded based on the signal application state of the relay and the relay output voltage; and
As a result of the determination, when welding of the relay contact is detected, applying a signal to the coil of the relay before the welding of the relay contact is cooled;
Method for preventing relay contact failure, including. According to clause 14,
A relay contact point in which welding of the relay contact point is detected when the signal applied to the coil of the relay is turned off and the voltage measured between the relay contact point and the rear end of the switch provided in the relay exceeds a predetermined high voltage judgment standard value. How to prevent breakdowns. According to clause 14,
A method for preventing relay contact failure, wherein when welding of the relay contact is detected, a signal is repeatedly applied to the coil of the relay a certain number of times until the welding phenomenon of the relay is removed. According to clause 16,
If the welding state is maintained even after repeatedly applying the signal a certain number of times,
recording a predetermined fault code indicating that a relay welding problem has occurred in a predetermined recording area; and
Transmitting a predetermined warning alarm indicating that a relay welding problem has occurred in the cluster through the in-vehicle communication network
A method for preventing relay contact failure, further comprising at least one of the following: According to clause 14,
Determining whether the switch contact of the relay has a defective current based on the signal application state of the relay and the relay output voltage; and
When a conduction failure at the switch contact is detected, controlling a large current to flow to the switch of the relay using a provided overcurrent conduction circuit.
A method for preventing relay contact failure, further comprising: A computer-readable recording medium recording a program for executing the method according to any one of claims 14 to 18.